Question

Write balanced half equations for the following reactions which take place at electrodes in electrolysis:

A) Cl^- → Cl2, O2^- → O2, F → F2
B) Cl2 → Cl^-, O2 → O2^-, F2 → F
C) Cl^- → Cl, O2^- → O2, F → F2
D) Cl2 → Cl, O2 → O2, F2 → F

Answer 1

Balanced half reactions involve writing separate equations for oxidation (anode reactions) and reduction (cathode reactions), where the electrons lost in oxidation are gained in reduction, ensuring the reactions are balanced for mass and charge.

Step-by-step explanation:

Writing Half Reactions for Electrolysis

To write balanced half equations for the reactions at electrodes during electrolysis, use the half-reaction method. For the anode (oxidation) reactions:

Chloride to chlorine: 2Cl- → Cl2 + 2e-

Oxide to oxygen: 4O2- → 2O2 + 4e-

Fluoride to fluorine: 2F- → F2 + 2e-

For the cathode (reduction) reactions:

Chlorine to chloride: Cl2 + 2e- → 2Cl-

Oxygen to oxide: O2 + 4e- → 2O2-

Fluorine to fluoride: F2 + 2e- → 2F-

It's important to ensure the equations are balanced for both mass and charge.